Cogeneration system

ABSTRACT

A Stirling engine-equipped cogeneration system is capable of utilizing thermal energy, without waste, and of offering high thermal usage efficiency at every stage of the thermal energy utilization process. The system includes a combustion chamber ( 11 ), a burner unit ( 5 ) installed to the combustion chamber, the burner unit driving combustion to generates exhaust gas within the combustion chamber, a liquid media jacket ( 21 ) that envelopes the combustion chamber, a liquid media flowing within the liquid media jacket and absorbing thermal energy from the burner-generated exhaust gas, a Stirling engine ( 4 ) operating from a sealed operating fluid heated by the heater ( 3 ) which is located within the combustion chamber facing the burner and subjected to the flow of exhaust gas generated within the combustion chamber, an exhaust gas flow channel ( 20 ) through which flows burner-generated exhaust gas after having flowed through and heating the heater, and an exhaust gas passage ( 22 ) having an entrance connected to the exhaust gas flow channel as means of allowing the exhaust gas to heat the liquid medium in the liquid media jacket. The exhaust gas generated from the burner-driven combustion flows into the heater to transfer thermal energy thereto, then flows into the exhaust gas passage, through the exhaust gas flow channel to transfer the thermal energy to the liquid medium, thereby heating the liquid medium and heater simultaneously.

TECHNICAL FIELD

The invention relates to a Stirling engine-equipped cogeneration systemthat does not waste thermal energy, and that offers superior energyutilization characteristics.

BACKGROUND ART

The invention relates to Stirling engine-equipped cogeneration system ofthe type, for example, disclosed in Related Art References (Tokkyobunken) 1 and 2.

Related Art Reference 1 discloses a cogeneration system assembled from ahydrogen storing heat pump and a Stirling engine equipped with anelectrical generator wherein the heater part of the Stirling engineincludes a heat-generating fuel-combusting burner located at the centerof the upper surface of the combustion case, and further includescombustion air passages being located at the upper wall of thecombustion case and leading from an external region to the flame orificeof the burner. In this cogeneration system, the thermal energy lost fromthe burner is 15% of the total (100%) input thermal energy.

Related Art Reference 2 describes a cogeneration system using acomposite Stirling and Rankine cycle and driving a compressor that heatslow-temperature steam and an electrical generator by the operation ofStirling engine. The heater of the Stirling engine is heated by air fedin from an air inlet port and heated by the combustion operation of theheat-generating burner, said heated air then being applied to a heatexchanging operation with air fed in from the air inlet port.

[Related Art Reference (Tokkyo bunken) 1]: Japanese Patent Laid-open(Kokai) Publication No. H7-279758 [pages 3-5, FIG. 1 and FIGS. 6-8]

[Related Art Reference (Tokkyo bunken) 2]: Japanese Patent Laid-open(Kokai) Publication No. 2000-213418 [pages 3-5, FIG. 1 and FIG. 5]

Both of the above-noted conventional cogeneration systems employ adedicated heating device to supply thermal energy to the Stirling engineheater, use the output of the Stirling engine to generate electricityfrom an electrical generator, and also use the obtained thermal energyto drive a hydrogen storing heat pump and compressor through a drivingstructure, thus they employ a mechanical structure to derive power fromthermal energy. This structure wastes a large amount of the thermalenergy generated by the thermal source, and therefore these cogenerationsystems cannot be said to use thermal energy efficiently.

DISCLOSURE OF THE INVENTION

The inventor, in consideration of the above-noted shortcoming, putsforth a Stirling engine-equipped cogeneration system able to completelyutilize thermal source energy with superior efficiency at the thermalenergy utilization process.

The cogeneration system invention includes a combustion chamber; aburner which is installed to the combustion chamber and induces anexhaust gas-generating combustion process within the combustion chamber;a liquid medium jacket which envelopes the combustion chamber andcontains a liquid medium flowing therein, the liquid medium being heatedby the exhaust gas generated by the burner; a Stirling engine which hasa heater installed within the combustion chamber and disposed inopposite to the burner so as to be struck by the flow of exhaust gas inthe combustion chamber, and is operated by means of being supplied athermal energy from the heater to an operating fluid sealed therein; anexhaust gas flow channel which discharges exhaust gas flowing toward theheater from the burner and supplying the thermal energy to the heater;and an exhaust gas passage which has an inlet connected to the exhaustgas flow channel and directs the flow of exhaust gas along the liquidmedium jacket, wherein the exhaust gas generated by the burner-drivencombustion flows against the heater in order to transfer the thermalenergy thereto, and flows into the exhaust gas passage, via the exhaustgas flow channel, in order to transfer the thermal energy to the liquidmedium, thereby providing a mechanism through which the exhaust gas isable to simultaneously transfer the thermal energy to the heater andliquid medium in order.

The cogeneration system invention is able to operate at an extremely lowlevel of thermal loss due to the below-noted structures and processes.The Stirling engine heater is installed within the combustion chamberwhich is heated by the burner-driven combustion, the liquid mediumjacket envelopes the combustion chamber, and the exhaust gas generatedby the burner-driven combustion flows against and heats the Stirlingengine heater which is disposed in opposition to the burner. Further,the exhaust gas also flows through the exhaust gas flow channel into theexhaust gas passage where it is applied to heat the liquid medium in theliquid medium jacket, thus allowing the liquid medium and heater to besimultaneously heated from a single combustion chamber. The heater andliquid medium, both which may be applied to a thermal utilizationprocess, are heated with a high level of efficiency without the thermallosses which would otherwise occur if the thermal energy were to betransferred through space, over time, or by mechanical means.

It is preferable that a casing is provided as means of enclosing atleast the heater of the Stirling engine and defining at least one ofspaces forming the combustion chamber.

It is preferable that an electrical generator is connected to an outputshaft of the Stirling engine.

It is preferable that a supply device is connected to the liquid mediumjacket as means of supplying the heated liquid medium to a thermalenergy utilization process.

It is preferable that a heat absorbing and discharging thermalaccumulator is installed within the combustion chamber.

It is preferable that the thermal accumulator is disposed in oppositionto the burner as means of allowing a burner flame and exhaust gasemitted from the burner-generated combustion to strike the thermalaccumulator.

It is preferable that a constricting part is installed in the combustionchamber to accelerate the flow of exhaust gas blown against the heater.

It is preferable that the Stirling engine is equipped with a regeneratoras means of cooling the operating fluid, and that a coolant heated bythe operating fluid through the operation of the regenerator heats theliquid medium.

It is preferable that an open and closable door is installed to thecombustion chamber as means of selectively exposing or sealing aninternal region of the combustion chamber.

It is preferable that the burner is attached to the door.

It is preferable that a removable lid is attached to the combustionchamber, and that the heater of the Stirling engine is attached to thelid.

It is preferable that various types of virgin oils, liquid refuse, wastegasses, solid waste materials, biomass fuels, or mixtures of any or allof these substances are used as fuel for the burner.

It is preferable that all types of virgin oils, liquid refuse, wastegasses, solid waste materials, biomass fuels, or mixtures of any or allof these substances are used as a base fuel material to which water isadded in order to make an aqueous emulsion fuel for supply to theburner.

It is preferable that the aqueous emulsion fuel is supplied to theburner from a fuel preparation unit, the fuel preparation unit includinga mixing and storing tank incorporating an agitator which agitates andmixes the base fuel material with water and a surfactant; an emulsifierwhich emulsifies the liquid mixture supplied from the mixing and storingtank; an ionizing unit that ionizes water molecules in the liquidmixture supplied from the emulsifier; and a pump that circulates theliquid mixture from the mixing and storing tank to the emulsifier, thento the ionizing unit, and then back to the mixing and storing tank.

It is preferable that an exhaust gas system of another process isconnected to the burner as means of re-combusting an exhaust gassesgenerated by another process.

It is preferable that the exhaust gas system is structured of two ductsystems, one duct system being connected directly to the burner, and theother duct system being connected to the burner through a washing devicewhich removes soot and ash from the exhaust gas.

It is preferable that a combustion gas supplied to the burner is in theform of a pure oxygen gas or an oxygen rich gas.

It is preferable that the fuel supplied to the burner is in the form ofa mixture of oxygen and hydrogen gas.

It is preferable that the burner includes an igniter; a nozzle with aspraying end that separately sprays out fuel and a primary gas which mixat a location external to the spraying end; a secondary gas supplysystem that sprays a secondary gas into a mixture of fuel and primarygas as means of imparting a spinning motion to the mixture of fuel andprimary gas; a gasification duct that gasifies the fuel in the spinningmixture of primary gas and fuel flowing therethrough; and an oxidizinggas supply passage which supplies oxidizing gas to an outlet of thegasification duct in order to ignite and combust the fuel.

It is preferable that the burner includes a double wall cylindricalstructure at the spraying end of the nozzle, the cylindrical structurebeing formed from an inner cylinder enclosed within an outer cylinder,the gasification duct being formed as a space within the inner cylinder,and the oxidizing gas supply passage being formed as a space within theouter cylinder.

It is preferable that an exhaust gas heating furnace is installed to theexhaust gas system.

It is preferable that the heating furnace is equipped with a combustionchamber through which exhaust gas flows, and a burner which is installedwithin the combustion chamber as means of combusting and heating theexhaust gas.

It is preferable that the fuel supplied to the burner is any type ofvirgin oils, a liquid state waste product, a gas state waste product, asolid state waste product, biomass fuel, or a mixture of any or all ofthese substances.

It is preferable that the fuel supplied to the burner is any type ofvirgin oils, a liquid state waste product, a gas state waste product, asolid state waste product, biomass fuel, or a mixture of any or all ofthese substances used as a base fuel to which water is added to make anaqueous emulsion fuel.

It is preferable that a combustion gas supplied to the burner is a pureoxygen gas or an oxygen rich gas.

It is preferable that the fuel supplied to the burner is a mixture ofoxygen and hydrogen gas.

It is preferable that the heating furnace is equipped with a Stirlingengine which has a heater installed within the combustion chamber andoperates from a thermal energy supplied by the heater heated by theburner-driven combustion, an output shaft of the Stirling engine beingconnected to an electrical generator.

It is preferable that a constricting part is installed within thecombustion chamber as means of accelerating the flow of exhaust gastherein against the heater.

It is preferable that a removable lid is attached to the heatingfurnace, and that the heater of the Stirling engine is attached to thelid.

It is preferable that an exhaust gas heating thermal plant is installedto the exhaust gas system, the thermal plant comprising a plurality ofheating furnaces mutually interconnected by ducts in an inlineconfiguration.

It is preferable that the thermal plant, in addition to the ductsinterconnecting a plurality of heating furnaces in the inlineconfiguration, is equipped with bypass ducts, each bypass duct bypassingeach heating furnace.

It is preferable that the heating furnace is equipped with a Stirlingengine which has a heater to be heated and operates from a thermalenergy supplied by the heater, an output shaft of the Stirling enginebeing connected to an electrical generator.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is further described in the detailed descriptionwhich follows, with reference to the below-noted plurality of drawingsrepresenting non-limiting examples of exemplary embodiments of thepresent invention in which like reference numerals represent similarparts throughout the several views of the drawings, and wherein

FIG. 1 is a cross section of a preferred embodiment of the cogenerationsystem invention;

FIG. 2 is a side view of the burner used by the FIG. 1 cogenerationsystem;

FIG. 3 is a side view of the double-wall pipe of the FIG. 2 burner;

FIG. 4 is a side view cross section of the tip region of the double-wallpipe shown in FIG. 3;

FIG. 5 is a side view of the nozzle body used by the FIG. 2 burner;

FIG. 6 is a side view of the aqueous emulsion fuel preparation unit usedby the FIG. 1 cogeneration system;

FIG. 7 is a side view cross section of the heating furnace which may beused by the FIG. 1 cogeneration system;

FIG. 8 is a system drawing of the thermal plant which may be used by theFIG. 1 cogeneration system; and

FIG. 9 is a cross section of another preferred embodiment of thecogeneration system invention.

BEST MODE FOR CARRYING OUT THE INVENTION

The following provides a detailed description of the preferredembodiments of the cogeneration system invention with reference to theattached figures. This embodiment of the cogeneration system 1, which isillustrated in FIG. 1, is primarily structured from boiler 2 which usesexhaust gas to heat a liquid medium [i.e., water] and extract thermalenergy therefrom, Stirling engine 4 which includes heater 3 and whichoperates from a sealed operating fluid heated by heater 3, and burnerunit 5 that serves as the thermal source from which thermal energy, thatis, combustion flames, the thermal radiation from those flames, andcombustion-generated exhaust gas, is supplied to boiler 2 and heater 3of Stirling engine 4. Output shaft 6 of Stirling engine 4 is connectedto electrical generator 7 as means of converting thermal energygenerated by heater 3 into electricity.

Stirling engine 4, electrical generator 7, and boiler 2 are mounted in ahorizontal orientation to frame 10, Stirling engine 4 and electricalgenerator 7 through framework 8, and boiler 2 through mounting leg 9.Burner unit 5 is also installed in a horizontal orientation. Thesecomponents may, of course, also be disposed in a vertical orientation.

Boiler 2 is equipped with inner cylinder 12 which forms a partitionedregion within combustion chamber 11 in which the air from burner unit 5is combusted, outer cylinder 13 which envelopes the outside of innercylinder 12 and forms the outer shell of boiler 2, and a pair of leftand right end plates 14 and 15 which are installed at the left and rightends of outer cylinder 13 and internal cylinder 12 to seal combustionchamber 11. Burner unit 5 and Stirling engine 4 are disposed at therespective left and right sides of boiler 2, thus sandwiching boiler 2therebetween. Burner unit 5 is attached to left end plate 14, and heater3 of Stirling engine 4 is attached to right end plate 15, thus orientingburner unit 5 and heater 3 in mutual opposition inside of combustionchamber 11, such disposition allowing heater 3 to be heated bycombustion from burner unit 5.

To be more specific, boiler 2 includes outer cylinder 13 having largediameter part 13 a on the left side which is the burner unit 5 side, andsmall diameter part 13 b on the right side which is the Stirling engine4 side, parts 13 a and 13 b being integral components of a singlestructure. Large diameter part 13 a is equipped with exhaust dischargeport 17 which is connected with exhaust duct 16 equipped with an exhaustgas processing induction fan drawing in exhaust gas and dischargesexhaust gas travels toward an exhaust gas treatment process through saidexhaust duct. Preheating passage 19, which is located at step wall 13 cbetween large diameter part 13 a and small diameter part 13 b, preheatsa liquid medium supplied to boiler 2 from a liquid supply device bymeans of a pump, with utilizing the thermal energy held in heataccumulator 27 (to be described subsequently).

Inner cylinder 12 includes large diameter part 12 a located at largediameter part 13 a of outer cylinder 13, and small diameter part 12 blocated at small diameter part 13 b of outer cylinder 13, small diameterpart 13 b forming a duct structure surrounding the front end of heater3. Large diameter part 12 a and small diameter part 12 b are formed asseparate components.

Cone 12 c forms a continuously narrowing passage extending from theright side of large diameter part 12 a toward small diameter part 12 b.The left end of small diameter part 12 b inserts into cone 12 c to forma continuous structure that accelerates the exhaust gas generated incombustion chamber 11 as said gas travels from burner unit 5 to andaround heater 3. Cone 12 c may also extend from the mouth at the leftend of small diameter part 12 b in a continually larger diameter towardthe mouth of large part 12 a which has a set diameter. Annular-shapedexhaust gas flow channel 20 is formed around the perimeter of small part12 b of inner cylinder 12, and between right end plate 15 and small part13 b of outer cylinder 13, as means of discharging exhaust gas flowinginto heater 3 from burner unit 5 via cone 12 c.

Liquid media jacket 21 surrounds combustion chamber 11 between largediameter part 13 a of outer cylinder 13 and large diameter part 12 a ofinner cylinder 12, and contains the flow of liquid medium heated byexhaust gas and thermal energy radiating from the inside of combustionchamber 11 as a result of the operation of burner unit 5. Also, exhaustgas passage 22 is provided as means of guiding the flow of exhaust gasto liquid media jacket 21. Liquid media jacket 21 connects to preheatingpassage 19 at the inlet port thereof and also connects to gas-liquidseparator 23, said gas-liquid separator being a device that supplies theheated liquid medium to a thermal utilization process. Gas-liquidseparator 23 separates the steam component from the liquid in liquidmedia jacket 21 and sends the steam component, as well as thehigh-temperature liquid component, to a thermal utilization process.

Therefore, the liquid medium, which is supplied to liquid media jacket21 from the liquid supply device via preheating passage 19, is heatedwithin liquid media jacket 21, and passes through gas-liquid separator23 as a gas and high-temperature liquid, and from there may be suppliedto any type of thermal utilization process. Moreover, Stirling engine 4,which is a known type of engine, is equipped with a regenerator whichcools the Stirling engine operating fluid. The regenerator is suppliedwith a coolant, such as water or other like substance, which is heatedas the result of a heat exchange operation with the operating fluid. Incase that the coolant heated by the regenerator flows through a pipe toa 3-way switching valve which connects to two pipes, one of the pipesbeing connected to preheating passage 19 through a heat exchanger, andthe other connected to a thermal utilization process, the operation ofthe 3-way switching valve makes effective usage of the thermal dischargefrom Stirling engine 4 possible by means of preheating the liquid mediumusing the heated coolant and applying the heated coolant to the thermalutilization process. Moreover, discharge drain pipe 24 is connected toliquid media jacket 21.

The inlet port of exhaust gas passage 22 connects to exhaust gas flowchannel 20 in which flows exhaust gas which has previously heated heater3, and the outlet port connects to discharge port 17 of outer cylinderlarge diameter part 13 a. Re-circulation passage 25 branches off fromexhaust gas passage 22 and is connected to combustion chamber 11 inorder to re-circulate a part of the exhaust gas coming from thecombustion flame draft of burner unit 5. Therefore, the exhaust gasgenerated from the combustion in burner unit 5 is accelerated throughcone 12 c, flows against and heats heater 3 which powers Stirling engine4, and then flows through exhaust gas flow channel 20 into exhaust gaspassage 22 to heat the liquid medium. One part of the exhaust gasreturning to combustion chamber 11 is re-combusted, and the remainingpart is sent from discharge port 17 to an exhaust gas process externalto the system for further processing.

Thermal accumulators 26 and 27 are located at appropriate locations inboiler 2 in order to absorb and radiate heat from the combustionoccurring in burner unit 5. Thermal accumulators 26 and 27, andespecially components residing within combustion chamber 11, are madefrom a fire and corrosion resistant material able to withstand thecombustion flames and corrosive effects of soot and ash generated fromthe combustion reaction taking place in burner unit 5. Moreover, innercylinder small diameter part 12 b is also made from a corrosionresistant material. In this embodiment, thermal accumulator 26 inside ofcombustion chamber 11 is located apart from cone 12 c, close to andopposing burner unit 5 in order to have both of the combustion flame andthe exhaust gas discharged from the flame of burner unit 5 strikeaccumulator 26. Also, heat accumulator 27 is removably attached to theinner surfaces of inner cylinder large part 12 a which forms the surfaceof combustion chamber 11, to left end plate 14, and to the innersurfaces of step wall 13 c.

Thermal accumulator 26 is structured from checker brick in whichthru-holes are formed as means of preventing the obstruction of exhaustgas flowing from burner unit 5. Thermal accumulator 26 is replaceablymounted on stage 28 which is fixedly installed within combustion chamber11. Thermal accumulators 26 and 27 become thermally saturated from thecombustion in burner unit 5, and are thus able to suppress temperaturefluctuations within combustion chamber 11, and to also heat, throughthermal radiation, the liquid medium in liquid media jacket 21 andpreheating channel 19.

In this embodiment of cogeneration system 1, the combustion flame,thermal radiation, and exhaust gas generated by the combustion in burnerunit 5 in combustion chamber 11 raise the temperature of heater 3 ofStirling engine 4 as well as the temperature of the liquid medium inboiler 2 through the flow of exhaust gas into exhaust gas passage 22through exhaust gas flow channel 20. These thermal operations are madepossible without moving or transporting heat through space or time whileat the same time generating both heat and electricity.

In addition, in this embodiment, left end plate 14, to which burner unit5 is attached, is attached to boiler 2 through a hinge, thus forming astructure through which left end plate 14 functions as an opening andclosing door through which the soot which accumulates in combustionchamber 11 may be removed, through which maintenance work can beconducted, and through which burner unit 5 can be taken out forinspection and maintenance at a location external to combustion chamber11.

Right end plate 15, to which heater 3 is attached, is structured as acover part which can be removed from outer cylinder small diameter part13 b by means of a coupling device. Moreover, framework 8, on whichStirling engine 4 and other components are mounted, is attached to frame10 through side rail 29. The removal of end plate 15 from outer cylindersmall diameter part 13 b and the slidable displacement of framework 8allow heater 3 to be pulled out of combustion chamber 11 formaintenance.

The following will describe burner unit 5 with reference to FIGS. 2, 3,4, and 5. Burner unit 5, which was developed by the inventors of thepresent invention, is a dual-flow misting-type burner unit [see Japanesepatent application No. 2002-382741] structured from;

double-wall pipe 32 which includes straightly formed fuel supply pipe 30and gas supply pipe 31 which surrounds the external side of fuel supplypipe 30, gas supply pipe 31 supplying a primary gas such as air;

mixing nozzle 33 which is attached to the tip of double-wall pipe 32 andwhich separately sprays out fuel and a primary gas from a spray tip soas to make them mix outside thereof, said fuel and primary gas beingrespectively supplied through fuel supply pipe 30 and gas supply pipe31;

double-wall cylinder 36 which provides a flame discharge orifice forwardof nozzle 33, cylinder 36 being structured from inner cylinder 34 andouter cylinder 35, both cylinder 34 and 35 being round in cross section;

low-flow fan 37 and high-flow fan 38 which draw in secondary gasses suchas air and the like, fan 37 being used for low combustion rates and fan38 for high combustion rates;

igniter 39; and

control unit 51 that controls the combustion process including initialignition, combustion, and combustion quench.

Fuel supply pipe 30 includes nozzle 33 connected to its tip part, andfuel solenoids 40 and 41 connected to its base part, solenoid 40controlling the fuel supply for a low combustion rate, and solenoid 41being an adjustable type controlling the fuel supply for a highcombustion rate. Fuel enters fuel supply pipe 30 through either solenoid40 or 41, and is sprayed out at high pressure from nozzle 33. The tippart of gas supply pipe 31 is connected to nozzle 33, and the base partthereof is provided with gas solenoids 42 and 43, solenoid 42controlling the supply of primary gas for a low combustion rate, andsolenoid 43 being an adjustable type controlling primary gas flow forhigh combustion rate. Primary gas also enters gas supply pipe 31 througheither solenoid 42 or 43, and is sprayed out from nozzle 33 at highpressure.

As shown in FIG. 4 and FIG. 5, nozzle 33, which is installed to the tippart of double-wall pipe 32, is primarily structured from hollowsleeve-shaped nozzle body 110 which connects to fuel supply pipe 30, andhollow sleeve-shaped nozzle cover 111 that surrounds nozzle body 110 andconnects to gas supply pipe 31. Nozzle body 110 is structured from(noted in sequence from the base part to the tip part) connecting part112 that threads into fuel supply pipe 30, first ring 113 which has alarger diameter than connecting part 112, pipe-shaped part 114 which hasa smaller diameter than connecting part 112, second ring 115 which has alarger diameter than pipe-shaped part 114 but a smaller diameter thanfirst ring 113, and fine pipe part 116 which extends beyond second ring115.

A threaded screw part is formed on the perimeter of first ring 113 andangular slits 117 are formed at appropriate intervals along thecircumferential direction thereon and incline to an axis of nozzle body110. Having much the same configuration as the first ring 113 structure,slits 118 are formed at appropriate intervals on the cone-shapedperimeter of the tip of second ring 115 which inclines to the axis ofnozzle body 110. Fuel spray passage 119 runs from connecting part 112through fine pipe part 116 in nozzle body 110 in order to introduce fuelinto fine pipe part 116 from fuel supply pipe 30 which connects toconnecting part 112, whereby fuel is sprayed out from fine pipe part116. Fuel spray passage 19 provides means of pressuring the fuel passingtherethrough by being formed to a diameter that decreases along itslength extending from connecting part 112 to fine pipe part 116.

Nozzle cover 111 includes, as noted in sequence from its base part toits tip part, connecting part 120 which forms a ring-shaped space aroundpipe-shaped part 114 of nozzle body 110, the inner perimeter ofconnecting part 120 threading into first ring 113 of nozzle body 110,and the outer perimeter threading into gas supply pipe 31; mid-section121 which is formed to a smaller diameter than connecting part 120 anddefines a narrow space around pipe-shaped part 114; and spray flange 124which is formed as a tapered cone-shaped tip part covering second ring115, defines gas spray chamber 122 around fine pipe part 116, and formsspray orifice 123, which connects to gas spray chamber 122 into whichfine pipe part 116 protrudes, from which fuel and primary gas aresprayed out.

Connecting part 120 installs against and around the perimeter of firstring 113, thus forming a structure able to impart a spinning motion tothe primary gas flow passing through slits 117. Passage is constructedbetween mid-section 121 and pipe-shaped part 114 to raise the pressureof the flowing primary gas. Spray flange 124 installs against thecone-shaped surface of second ring 115, thus forming a structure able tostrengthen a spinning motion to the primary gas flow passing throughslits 118. Nozzle 33 may, for example, be assembled through a structurewhereby nozzle body 110 is inserted and tightened into nozzle cover 111after which nozzle body 110 is tightened to fuel supply pipe 30 andnozzle cover 111 is tightened to gas supply pipe 31.

The gas flowing through gas passage 125 between nozzle cover 111 andnozzle body 110 (gas passage 125 being formed as a continuous passagefrom gas supply pipe 31 to spray orifice 123) is driven in a spinningmotion by slits 117 of first ring 113 after which the pressure of theflowing gas is increased by the constricting effect applied bymid-section 121, and the spinning motion further strengthened by slits118 of second ring 115. Finally, the fuel is sprayed out from fine pipepart 116 of nozzle body 110 and the primary gas is sprayed out from gasspray chamber 122 through spray orifice 123 as the high-speed spinningand shearing flow, whereby the fuel is mixed with and very finelyatomized by the primary gas outside of nozzle 33.

Cylindrical wind box 45 is installed around the tip of nozzle 33 throughwhich the fuel and primary gas mixture, as mixed in the previouslydescribed process, is sprayed. Inverter-controlled high-flow fan 38,which draws in secondary gas supplied to wind box 45, is joined to windbox 45 via duct arranged in the tangential direction of wind box 45.High-flow fan 38, duct 46, and wind box 45 have the function of furtherpromoting the mixing of the fuel and primary gas mixture through acircular flow path. The induction of a secondary gas in this mannerdrives the mixture of fuel and primary gas (which has been sprayed outfrom nozzle 33) with a high-speed circular motion which has the effectof ultra-atomizing the fuel under ultra-mixture condition.

Moreover, double wall cylinder 36 is installed to the opposite side ofwind box 45 from double-wall pipe 32. Inner cylinder 34 of double wallcylinder 36 forms a fuel gasification duct in which the fuel is gasifiedas the gas-fuel mixture moves therethrough with a spinning motion. Inorder to ignite and combust the fuel, outer cylinder 35 functions as anoxidation gas supply passage through which oxidation gas passes towardthe exit orifice of inner cylinder 34 which extends outward from the endof outer cylinder 35. In this embodiment, outer cylinder 35 isstructured to form a connecting passage to wind box 45 allowing part ofthe secondary gas, which serves as the oxidation gas, to flow throughouter cylinder 35. Furthermore, a structure may be employed which doesnot limit the gasification of fuel to a mechanism thorough which thefuel is gasified after exiting nozzle 33, but which may supplypreviously gasified fuel, through fuel pipe 30, to be sprayed fromnozzle 33.

Igniter 39 is applied to an ignition method to light a pilot flame onpilot burner 47 which is disposed parallel to double-wall pipe 32 andextends to the tip of the nozzle. In other words, pilot flame electrode49, which is connected to pilot flame transformer 48, emits anelectrical discharge that ignites a pilot flame fed by the fuel gasdischarged from pilot burner 47 after which fuel sprayed out of nozzle33 is ignited by the pilot flame. Low-flow fan 37, which is installedbehind nozzle 33, supplies secondary gas at a low flow rate during a lowrate combustion condition after the mixture has ignited. Light fuel oilor other like substance, or both fuel gas and light fuel oil, may beused in place of fuel gas for this purpose. Furthermore, flame sensor50, which is installed to burner unit 5, automatically functions as asensor for detecting an emergency, outputting a warning and sending afault condition signal to controller 51 in order to stop the combustionoperation.

To explain the operation of burner unit 5, after a pilot flame is lit atigniter 39, fuel solenoids 40 and 42 open to supply fuel and primary gasto nozzle 33 through fuel supply pipe 30 and gas supply pipe 31.Low-flow fan 37 then begins operation by blowing in a small amount ofsecondary gas which ignites and thus initiates low rate combustion.

Next, high rate combustion initiates by fuel solenoid 41 and gassolenoid 43 gradually opening while high-flow fan 38 blows in a largeramount of air. The secondary gas effectively intermixes with the fueland primary gas sprayed from nozzle 33, while ultra-atomizing the fuelunder the spinning motion at a high rate of speed, and sends the fueland primary gas to inner cylinder 34 to promote the gasification of thefuel. During this process, a part of the still spinning secondary gasflows into outer cylinder 35 and is blown out from the exit orifice ofdouble-wall cylinder 36.

The secondary gas blown out of outer cylinder 35 mixes with the gasifiedfuel at the exit orifice of inner cylinder 34 and combusts, thus it iscreated a stable, high-rate, and complete combustion condition. Inparticular, if water is mixed in with the fuel, it becomes possible toinduce an aqueous gasification reaction within inner cylinder 34, and anoxidation reaction with the secondary gas emitted from outer cylinder 35at the exit orifice of inner cylinder 34, thus generating an explosivecombustion condition. In this high-rate combustion process, a step-lessturn-down control system may be conducted through the adjustableoperation of solenoids 41 and 43 and inverter controlled adjustableoperation of high-flow fan 38.

Burner unit 5 may use various types of fuel including kerosene, heavyfuel oil, vegetable oil, mineral oil and the like. Fuel types are notlimited to virgin oils, but may also include used oils, high water-cutoils, liquid waste, oil processed from waste plastics, biomass fuelssuch as wood vinegar pyroligneous acid derived from drying bamboo and soforth, and waste gases such as exhaust gas. Fuel can also take the formof liquids into which particles and powders processed from solid wasteand biomass substances have been mixed, mixtures of the above-notedsubstances, and aqueous emulsion fuels made by mixing water into basematerials made from the above-noted substances. The aqueous component ofthese fuels may be clean or it may contain impurities.

The use of aqueous emulsion fuels enables an aqueous gas reactionthrough which burner unit 5 is able to operate at high efficiency, andthus promote complete combustion which has the effect of purifying theexhaust gas. The gas supplied to burner unit 5 may, of course, be air,or it may be a combustible gas. Exhaust gases may be supplied forre-combustion as a result of the excellent combustion characteristics ofburner unit 5 which is able to thermally separate fuel components athigh temperatures. In addition, the structure of nozzle 33 allows theuse of high viscosity fuels as well as low viscosity types.

Also, by supplying and burning a mixture of oxygen and hydrogen, theresulting high temperature inhibits the generation of toxic componentsand eliminates exhaust gas. Moreover, a high temperature low NOxcombustion process may be ensured by using pure oxygen or an oxygen richgas as the combustion gas and supplying it to burner unit 5 as a singlegas or in combination with other gasses. A gas including oxygen and/orhydrogen components may also be combusted in addition to the above-notedsubstances.

The following will describe, with reference to FIG. 6, an aqueousemulsion fuel which can be supplied to burner unit 5 and combusted, andfuel preparation unit 62 which manufactures the aforesaid aqueousemulsion fuel. Aqueous emulsion fuel and fuel preparation unit 62 havebeen developed by the inventor of the present invention (disclosed inJapanese Patent Application No. 2001-282360). Fuel preparation unit 62includes;

oil tank 52 which stores oil such as waste oil;

water supply valve 53 which opens and closes to adjustably control thesupply of utility-supplied water to a water pipe;

a surfactant tank storing a surfactant which promotes and stabilizesemulsification;

mixing tank 55 which stores a mixture of waste oil, surfactant andwater, said waste oil and surfactant being respectively supplied fromadjusting valve-installed pipes connected to oil tank 52 and thesurfactant tank, and said water being supplied through water supplyvalve 53;

agitator 56, installed to mixing tank 55, which creates a liquidmixture;

emulsifier 57 which attenuates clusters in the mixture liquid suppliedfrom mixing tank 55 by applying a water impact process (through whichthe liquid mixture is broken down) and a process contacting withcrystals, in order to promote emulsification of the liquid mixture;

ionizing unit 58 which generates a magnetic field of intersectingmagnetic force lines to ionize the liquid component of the liquidmixture supplied from emulsifier 57;

circulation pump 59 that draws the liquid mixture from mixing tank 55and circulates it back to tank 55 through a closed loop pipe systemconnecting mixing tank 55, emulsifier 57, and ionizing unit 58; and

automatic controller 54 that controls the fuel emulsification process.

When preparing an aqueous emulsion fuel, one part waste oil and one partutility-supplied water are placed in mixing tank 55 along with asurfactant which is added at a volume of 0.1˜0.7% of the total. Whileagitator 56 is operating, pump 59 circulates the mixture from mixingtank 55, under pressure, through emulsifier 57 and ionizing unit 58which has the effect, over a period of time, of creating a stablewater-fuel emulsion. This type of fuel manufacturing process isautomatically controlled through automatic controller 54.

The prepared aqueous emulsion fuel is then deposited in reserve tank 60by switching the fuel flow at the output side [emulsifier side] of pump59 to reserve tank 60. Reserve tank 60 is connected to fuel supply pipe30 of burner unit 5 through a pipe connected to oil pump 61 whichintermittently supplies burner unit 5 with the manufactured aqueousemulsion fuel with excess fuel returning to reserve tank 60.

The surfactant may be added to the mixture through an additive unitinstalled between mixing tank 55 and pump 59. Also, a water holding tankmay be installed with the purpose of supplying water to mixing tank 55.While this description has specified a 1:1 mixture of waste oil andwater, the water component may occupy up to 90% volume of the mixture.The aqueous emulsion fuel, as prepared by this process, is slow toevaporate at normal temperatures, and is able to be transported andstored with a high level of safety due to its high ignition temperature.

This embodiment of the above-described fuel preparation unit 62, whichincludes emulsifier 57 and magnetic field-generating ionizing unit 58[both of which need not be externally powered], pump 59, tanks 52, 24,55, and 60, pipes, and other like components, is a simple structurecapable of easily preparing an aqueous emulsion fuel at low cost.

Moreover, in this embodiment, exhaust gas system 63 communicated withanother process is connected to high-flow fan 38 of burner unit 5 tosupply the exhaust gas, as the secondary gas, to burner unit 5 fromanother process. This secondary exhaust gas, as has been previouslydescribed, accelerates and is mixed into the spinning flow proximal tonozzle 33, and is blown out from outer cylinder 35, to provide anexhaust gas re-combustion process.

Exhaust gas system 63 is divided into two systems, one including firstexhaust gas duct 64 through which flows exhaust gas containing a largeamount of soot and other foreign objects, and the second includingsecond exhaust gas duct 65 through which flows exhaust gas containing asmall amount of foreign objects. Second exhaust gas duct 65 connectsdirectly to high-flow fan 38, and first exhaust gas duct 64 connects tohigh-flow fan 38 through heat exchanger 66 which is located betweenfirst exhaust gas duct 64 and exhaust duct 16 through which exhaust gasflows. Heat exchanger 66, which is disposed between exhaust duct 16 andfirst exhaust gas duct 64, includes an internally installed sootcollector which removes solid objects from the exhaust gas flowingthrough first exhaust gas duct 64. Also, one of three stop valves 67through 69 is installed on the intake side of fan 38 of second exhaustgas duct 65, and on the intake and exhaust sides of heat exchanger 66 offirst exhaust gas duct 64.

Exhaust gas may be drawn through exhaust gas system 63 by high-flow fan38 in the following manner. When exhaust gas is flowing through firstexhaust gas duct 64, first stop valve 67 in second exhaust gas duct 65is closed, and second and third stop valves 68 and 69 on the heatexchanger 66 side are open. Conversely, when exhaust gas is flowingthrough second exhaust gas duct 65, first stop valve 67 in secondexhaust gas duct 65 is open, and second and third stop valve 68 and 69are closed. Adjustment valve 70 is installed to exhaust duct 16 tocontrol the discharge pressure of heat exchanger 66 so as to adjust thecombustion pressure within combustion chamber 11.

To explain the operation of this embodiment of cogeneration system 1,operation starts with the ignition of burner unit 5 and the supply offuel to burner unit 5 from fuel preparation unit 62, followed by thesupply of exhaust gas, which serves as the secondary gas, from exhaustgas system 63, the supply of secondary gas resulting in burner unit 5moving from a low combustion rate to a high combustion rate. Thecombustion is generated by burner unit 5, the heat is stored in thermalaccumulators 26 and 27, and the exhaust gas circulating within boiler 2transfers thermal energy to heater 3 and the liquid medium. Therefore,Stirling engine 4 begins operation when heater 3 reaches a presettemperature and electrical generator 7, which is driven by Stirlingengine 4, initiates the generation of electricity while the heatedliquid medium is supplied from gas-liquid separator 23 to the thermalutilization processes, this making it possible to provide two energysources.

Cogeneration system 1 of this embodiment specifies that heater 3 ofStirling engine 4 being installed within combustion chamber 11 which isthermally energized by the combustion propagated by burner unit 5 andliquid media jacket 21 which surrounds combustion chamber 11. Theexhaust gas generated by the combustion from burner unit 5 flows overand imparts thermal energy to heater 3 of Stirling engine 4 beingopposite to burner unit 5, and sequentially heats the liquid medium inmedium jacket 21 by flowing into exhaust gas passage 22 through exhaustgas flow channel. Because the liquid medium and heater 3 are heatedwithin a single combustion chamber 11 at the almost same time, there isno need to provide space, time, or mechanical means to transfer thermalenergy in order to heat heater 3 and the liquid medium. Therefore,thermal energy loss is reduced, heater 3 and the thermal utilizationliquid medium are more efficiently heated from combustion driven byburner unit 5, and cogeneration system 1 operates without wastingenergy.

In addition to high thermal utilization efficiency, this embodiment ofthe cogeneration system 1 combines boiler 2 and Stirling engine 4 into asingle assembly which forms a more compact structure. The cogenerationsystem 1 is able to offer superior performance, especially when appliedas a zone-type cogeneration system, due to boiler 2 and Stirling engine4 not requiring their own heat source, and by boiler 2 and Stirlingengine 4 being able to generate energy from various types of fuels thatmay even contain a variety of waste materials.

The cogeneration of both electrical and thermal energy is made possibleby Stirling engine 4 driving electrical generator 7, and by the liquidmedium being supplied to a thermal utilization process. The installationof thermal accumulators 26 and 27 (which draw in and discharge heat)within combustion chamber 11 make it possible to control temperaturefluctuations in combustion chamber 11 and to stabilize the heatingprocess through which thermal energy is transferred to heater 3 and theliquid medium at a set temperature. As a result of the flames andexhaust gas discharged from burner unit 5 striking oppositely disposedthermal accumulator 26, it becomes possible for thermal accumulator 26to store thermal energy at the highest temperature of the combustionconducted by burner unit 5, thus allowing the maximum amount ofcombustion energy from burner unit 5 to be transferred to heater 3 andthe liquid medium.

Even though both the liquid medium and heater 3 are heated through asingle combustion chamber 11 simultaneously, the exhaust gas iseffectively collected and supplied to heater 3 through cone 12 c whichis disposed in opposition thereto, thus forming a mechanism throughwhich thermal energy is efficiently transferred to heater 3, and throughwhich the efficient operation of Stirling engine 4 can be maintained attemperatures from 750˜800° C. Moreover, the coolant heated by theoperation of the regenerator of Stirling engine 4 may be applied to heatthe liquid medium or may be supplied to the heat utilization process.This process allows the heat discharged by Stirling engine 4, that is,part of the heat originating from the combustion within burner unit 5,to also be applied as the thermal energy to further increase theutilization of thermal energy from burner unit 5.

Left end plate 14, which also functions as a door, may open to allowaccess to the internal region of combustion chamber 11 from whichaccumulated soot may be easily removed and in which other maintenanceoperations may be conducted. Moreover, the attachment of burner unit 5to end plate 14 results in burner unit 5 swinging out of combustionchamber 11 when end plate 14 is opened, thus allowing convenientmaintenance of burner unit 5. Conversely, right end plate 15 functionsas a lid to which heater 3 of Stirling engine 4 is attached, the removalof end plate 15 exposing heater 3 to the external environment forconvenient maintenance and repair work.

The fuel supplied to burner unit 5 may take the form of various types ofvirgin oils, liquid waste products, gaseous waste products, solid statewaste products, biomass fuels and a mixture made of some of them, inaddition to normal sulphonated petroleum oils, vegetable oils, andmineral oils, because boiler 2 and Stirling engine 4 as anexternal-combustion engine is characterized by being able to operated bya variety of fuels. The cogeneration system is thus structured to usewaste products as fuel, and in doing so promotes the re-cycling of wasteproducts and protection of the environment.

Moreover, the cogeneration system invention is able to promote thereduction of industrial waste products and the recycling of resourcesbecause burner unit 5 may be supplied with the aqueous emulsion fuelwhich is made by adding water to the base fuel substances such as avarious types of virgin oils, liquid waste products, gaseous wasteproducts, solid state waste products, biomass fuels and the mixture madeof some of them. Namely, the system can be operated by the highcombustion performance of the aqueous emulsion fuel and theabove-mentioned characteristics of both of the boiler 2 and Stirlingengine 4, even though the base fuel substances contains the wasteproducts.

Moreover, the fuel preparation unit, which is a simple structureconstructed from mixing tank 55, agitator 56 installed to mixing tank55, emulsifier 57, ionizing unit 58, and pump 59, is able toeconomically prepare aqueous emulsion fuels.

Exhaust gas in the form of a gaseous state waste product may be suppliedto burner unit 5 and washed through the re-combustion process.Furthermore, exhaust gas system 63, which supplies exhaust gas to burnerunit 5, is structured from first and second exhaust gas ducts 64 and 65,second exhaust gas duct being directly connected to burner unit 5, andfirst exhaust gas duct 64 being connected to burner unit 5 through sootremoving soot collector. The reliable operation of burner unit 5 isimproved as a result of the soot collector removing soot from exhaustgas before said gas is supplied to burner unit 5.

The combustion gas supplied to burner unit 5 may take the form of pureoxygen gas or an oxygen-rich gas, thus making it possible to run a lowNOx combustion process. Moreover, the fuel supplied to burner unit 5 mayalso be a mixture of oxygen and hydrogen, thus making it possible toprevent the generation of toxic pollution components through acompletely clean combustion process. Other substances may, of course, bemixed in with these fuel gasses and combusted.

Moreover, burner unit 5 heats boiler 2 and heater 3 by completelycombusting waste products which may be used as fuel, or aqueous emulsionfuels containing waste products. This is made possible by the structureof nozzle 33 which is able to separately spray out fuel and primary gaswhich are mixed external to the spray tip of nozzle 33, wind box 45, fan38 and duct 46 which introduce a secondary gas into the fuel and primarygas mixture to impart a spinning motion to the mixture, inner cylinder34 which serves as a fuel gasification duct for the spinning fuel andgas mixture flowing therethrough, and outer cylinder 35 which serves asan oxidation gas passage supplying oxidation gas to the discharge end ofinner cylinder 34 in order to ignite and combust the fuel.

When an aqueous emulsion fuel is burned, an aqueous gas reaction isinduced resulting in a continuous, stable, high-temperature explosivecombustion process. Moreover, complete combustion may be obtained, evenin the presence of low air reaction, as a result of the supplementationof the required oxygen. Therefore, this combustion process reduces fuelexpenses by minimizing thermal loss, maintaining a dependable andeconomical low-energy combustion, suppressing the generation of sootthrough complete combustion at high temperatures, and minimizing theproduction of NOx, SOx, CO, Co2, and other atmospheric pollutants so asnot to contribute to global warming.

Therefore, sufficient combustion heat is obtained from the aqueous gasreaction to support the operation of Stirling engine 4 which operates ina temperature range of from 750˜800° C., and because thermal loss fromStirling engine 4 is extremely small, the liquid medium in boiler 2 canbe heated to a sufficiently high temperature. Also, the use of aqueousemulsion fuels to cogeneration system 1 makes it possible to attain afuel processing thermal cycle in which the previously noted multipletypes of low grade waste materials may be used as a source of thermalenergy.

Moreover, burner unit 5 is made to compact dimensions by means of beingstructured to include a double wall cylindrical assembly of innercylinder 34 and outer cylinder 35 which respectively serve asgasification and oxygenation gas supply ducts. Due to the processthrough which an oxidation gas is supplied through the outer cylinder 35while an aqueous gasification reaction occurs at the inner cylinder 34,a complete high-temperature combustion process is made possible throughan oxidation combustion reaction of high efficiency and minimal thermalloss.

Moreover, the combustion taking place in combustion chamber 11eliminates the need for the normally used exhaust gas processinginduction fan in exhaust duct 16.

FIG. 7 illustrates heating furnace 71 which may be preferably assembledwith the previously described cogeneration system 1 embodiment. Heatingfurnace 71 is connected to exhaust gas system 63, for example to secondexhaust gas duct 65 to heat the exhaust gas therethrough.

Heating furnace 71 is primarily structured from;

equipment supporting frame structure 72;

vertical housing 75 which is attached to frame structure 72, formscombustion chamber 74 through which exhaust gas flows, and to whichthermal accumulator 73 having a flame and corrosion resistant propertyis installed at the internal surface thereof;

vortex flame burner 77 installed within vertical housing 75, burner 77operating to combust exhaust gasses while imparting a vortex-likespinning flow pattern to the combustion flame which is blown upward,along with combustion air, by fan 76 which is attached to the externalpart of vertical housing 75;

Stirling engine 80 installed in a vertical orientation above top plate78 of vertical housing 75, heater 79 of Stirling engine 80 beingdisposed within combustion chamber 74 facing vortex flame burner 77;

electrical generator 82 which is connected to the output shaft 81 ofStirling engine 80;

cone member 83 which is installed within the upper region of combustionchamber 74, the inner surface of cone member 83 extending toward heater79 to form a constricting cone-like structure which accelerates exhaustgas blown toward heater 79;

exhaust gas port 84 which is formed at the upper region of verticalhousing 75 and connects to the open space between cone member 83 and topplate 78, and which directs the exhaust gas to second exhaust gas duct65;

adjustment valve 85 which is installed in the vicinity of exhaust gasport 84 and which is controllably opened and closed to adjust theexhaust gas flow rate to maintain an approximately uniform temperaturewithin combustion chamber 74;

preheating tank 86 which is installed external to vertical housing 75and which stores and pre-heats the fuel supplied to vortex flame burner77 by accumulating heat radiated from vertical housing 75;

oil supply pipe 87 which is connected to preheating tank 86, runsthrough vertical housing 75, extends above and faces vortex flame burner77, and drops fuel, supplied from preheating tank 86, down onto flameburner 77 by operation of the cock;

heat resistant gas supply fan 89 which is attached to vertical housing75, and which blows exhaust gas from another process into the internalregion of vertical housing 75 through supply duct 88 whose opening islocated between vortex flame burner 77 and oil supply pipe 87;

exhaust gas intake duct 91 which supplies exhaust gas from anotherprocess to fan 89 through adjusting valve 90;

temperature adjusting duct 93 which is connected to exhaust gas intakeduct 91, duct 93 being equipped with adjusting valve 92 which directsair into the flow of exhaust gas in order to adjust the exhaust gastemperature; and

oxygen supply duct 94 which connects to supply duct 88 and supplies arequired amount of oxygen, from an oxygen condenser, which mixes in withthe exhaust gas as means of inducing high-temperature oxygen-richcombustion.

Stirling engine 80 and electrical generator 82 are able to slidevertically upward or downward on frame structure 72 through sliding base95. Furthermore, top plate 78 is structured as a cover removablyattached to the top of vertical housing 75 in which heater 79 isinstalled. Removing top plate 78 and lifting up sliding base 95 alongframe structure 72 allows access to heater 79 which can be pulled out ofcombustion chamber 74 for maintenance work. Furthermore, stopper 96 isprovided on frame structure 72, to limit the downward travel of slidingbase 95.

In heating furnace 71, vortex flame burner 77 combusts the fuel,combustion air, exhaust gas, and if necessary, oxygen which results inthe generation of thermal energy and exhaust gas which is applied toheater 79 to drive Stirling engine 80 which in turn powers electricalgenerator 82 to generate electricity while combustion-heated hightemperature exhaust gas is concurrently supplied to burner unit 5through exhaust gas system 63. Supplying this large amount of thermalenergy and high-temperature exhaust gas to burner unit 5 allows thecombustion process to operate with a high degree of combustionefficiency. In cases where little heat is applied to burner unit 5, theaddition of an exhaust gas makes it possible for cogeneration system 1to operate with high efficiency. Furthermore, by using burner 77 to heatthe exhaust gas, an exhaust gas combustion process is enabled whichmakes it possible to remove, or “wash” undesirable components from theexhaust gas.

Heating furnace 71 may incorporate Stirling engine 80 to driveelectrical generator 82, thus making heating furnace 71 electricitygenerating cogeneration system in itself. More specifically, it becomespossible to maintain the exhaust gas supplied to burner unit 5, fromcombustion chamber 74, at a high temperature due to the high efficiencyand minimal thermal loss with which a Stirling engine operates. Also,cone member 83 in combustion chamber 74 collects and focuses the exhaustgas on heater 79, and therefore thermal energy is efficientlytransferred to heater 79 to assure that Stirling engine 80 is able tooperate with a high degree of efficiency.

Removing top plate 78 of vertical housing 75 exposes heater 79 to theregion external to combustion chamber 74, thus allowing maintenance tobe performed on heater 79 in an easily accessible position.

The method through which fuel is supplied to vortex flame burner 77 ofheating furnace 71 is, in the same manner as previously described inregard to the fuel supplied to burner unit 5, designed to promote therecycling and reduction of waste products in order to contribute toenvironmental conservation. Heating furnace 71 is able to pre-heat thefuel supplied therein from pre-heating tank 86, therefore heatingfurnace 71 is able to liquidize incoming fuel, a factor that allows theuse of high viscosity fuels. In addition, a clean combustion process isassured by supplying burner 77 with a combustion gas such as oxygen gas,oxygen-rich gas, or a mixture of oxygen and hydrogen gas from oxygensupply duct 94 in the same manner as previously described in regard toburner unit 5. Other substances may, of course, be mixed into theaforesaid gasses.

FIG. 8 illustrates an embodiment of cogeneration system 1 in the form ofthermal plant 97 structured from an array of multiple heating furnaces71 (each furnace 71 shown in detail in FIG. 7) joined in an inlineconfiguration by connecting duct 98, thus making it possible to heateach of the exhaust gas generated by other plants individually and toprocess said exhaust gas through multiple heating cycles.

As FIG. 8 illustrates, the upper portion of each heating furnace 71incorporates a gas supply port 99 opposing an exhaust gas port 84, theexhaust gas port 84 of each heating furnace 71 being connected to thegas supply port 99 of the adjacent heating furnace 71 by connecting duct98, thus forming a structure allowing the exhaust gas discharged fromeach heating furnace 71 to flow from an upstream side to a downstreamside therebetween. Second exhaust gas duct 65 is formed by theconnection of exhaust gas port 84 of the last downstream heating furnace71 to high-flow fan 38 of burner unit 5 through connecting duct 98, andthe connection of all heating furnaces 71 through connecting duct 98.

Therefore, thermal plant 97 includes the aforesaid first exhaust gasduct 64, which is provided as a bypass duct bypassing each heatingfurnace 71, in addition to second exhaust gas duct 65. A stop valve 100is installed in each connecting duct 101 installed between the first andsecond exhaust gas ducts 64 and 65 between each heating furnace 71, andin the connecting duct 101 located between heating furnace 71 and burnerunit 5.

Firstly, by opening each adjustment valve 85 in second exhaust gas duct65, and by closing each stop valve 100 in each connecting duct 101, theexhaust gas flow is routed through the second exhaust gas duct 65 andthus through each heating furnace 71. Secondly, by closing any of theadjustment valves 85 in second exhaust gas duct 65, and by opening astop valve 100 in connecting duct 101 on the upstream side of the closedadjustment valve 85, it becomes possible to route the flow of exhaustgas, through the operation of an upstream heating furnace 71, from thesecond exhaust gas duct 65 to first exhaust gas duct 64. Thirdly, evenwhen the exhaust gas flow is routed from second exhaust gas duct 65 tofirst exhaust gas duct 64, closing second stop valve 68 on the intakeside of heat exchanger 66, while a stop valve 100 in connecting duct 101is open, makes it possible to route the flow of exhaust gas back tosecond exhaust gas duct 65.

In other words, the selective operation of valves 85 and 100 inconnecting ducts 98 and 101, along with the selective operation of theaforesaid first, second, and third stop valves 67, 68, and 69, makes itpossible to control the number of heating furnaces 71 to which exhaustgas is supplied, that is, to route the flow of exhaust gas around aspecific heating furnace 71 if desired, thus allowing maintenance andrepair work to be done on the bypassed heating furnace 71 withoutinterrupting the continuing operation of thermal plant 97. Therefore,when the temperature of the exhaust gas supplied to burner unit 5 is toolow and must be raised, the exhaust gas flow may be routed through therequired number of heating furnaces 71 through second exhaust gas duct65 and heated by each vortex flame burner 77. Conversely, when theexhaust gas temperature is effectively high, the exhaust gas flow may berouted around a heating furnace 71 through first exhaust gas duct 64.Therefore, in cases where the exhaust gas contains a large amount ofdebris, first stop valve 67 may be closed to route the gas flow throughfirst exhaust gas duct 64.

Providing thermal plant 97 as means of heating the exhaust gas flowingthrough exhaust gas system 63, and structuring thermal plant 97 toinclude multiple heating furnaces 71 connected in series throughconnecting ducts 98, makes it possible to maintain the exhaust gas,which is cooled as it travels through exhaust gas system 63, at therequired high temperature constantly, to raise the thermal volume of theexhaust gas supplied to burner unit 5, and to have burner unit 5generate a highly efficient combustion process. Also, this structuremakes it possible to divert exhaust gas from heating furnace 71 throughfirst exhaust gas duct 64 which serves as a bypass duct, to run or toshut down each heating furnace 71 as desired, to determine how manyheating furnaces 71 will operate, and to keep cogeneration system 1running even when one or more of the heating furnaces 71 are shut downfor maintenance or repair work.

Therefore, thermal plant 97 may also be applied as a cogeneration systemable to generate electricity by having Stirling engine 80 driveelectrical generator 82. Thermal plant 97 makes it possible to maintainthe temperature of the exhaust gas supplied to burner unit 5 due to theStirling engine's high operating efficiency and low thermal loss, tosimultaneously generate electricity through the multiple Stirlingengines 80 powered by the combustion heat and exhaust gas produced bythe vortex flame burner 77 of each heating furnace 71, and lastly todrive Stirling engine 4 through the operation of boiler 2 whileconcurrently recycling thermal energy, through the liquid medium, to athermal utilization plant.

Also, it is preferable that heating furnace 71 and thermal plant 97(which is equipped with multiple heating furnaces 71) send the coolant,which has been heated by the operation of the regenerator of Stirlingengine 80, to another thermal utilization process, thus providing aprocess able to effectively use the discharge heat from Stirling engine4 as thermal energy.

FIG. 9 illustrates another preferred embodiment of cogeneration system1. In this embodiment of cogeneration system 1, Stirling engine 4 (whichincludes heater 3) and electrical generator 7 are installed in casing102, and heater 3 is located in cavity 103 defined within casing 102.

As a result of this embodiment placing heater 3 within casing 102,combustion chamber 11 is formed into partitioned regions which includecavity 103, large diameter part 12 a of inner cylinder 12, constrictingcone part 104 put in place of cone 12 b and separately structured largediameter part 12 a, and first duct 105 which connects boiler 2 andcasing 102 through a passage formed between cone part 104 and cavity103, first duct 105 and cavity 103 form a structure which corresponds tosmall diameter part 12 b of inner cylinder 12 described in the previousembodiment. As a result, a single combustion chamber 11 (which isenveloped by liquid media jacket 21 and heated by combustion from burnerunit 5) extends from large diameter part 12 a of inner cylinder 12 up tocavity 103 via first duct 105. To explain further, combustion chamber 11is formed as a continuing chamber extending from outer cylinder 13 up tocasing 102. In other words, casing 102 divides combustion chamber 11into compartments. Furthermore, first duct 105 is formed as a pair ofmutually disconnectable duct members 105 a, one of which is an extendingpart opposing end wall 13 d of outer cylinder 13 (end wall 13 d beingused in place of step wall 13 c), and the other as an extending partopposing casing 102.

Moreover, this embodiment eliminates small diameter part 13 b of outercylinder 13 in the previous embodiment, and replaces exhaust gas flowchannel 20 (which, in the previous embodiment, connects the regionaround heater 3 with exhaust gas passage 22) with second duct 106 whichconnects cavity 103 on the casing 102 side with exhaust gas passage 22on the outer cylinder 13 side. Second duct 106 is also structured from apair of duct members 106 a, one of which is formed as an extending partopposing end wall 13 d of outer cylinder 13, and the other as anextending part opposing casing 102.

Furthermore, in addition to eliminating small diameter part 13 b ofouter cylinder 13 which houses heater 3 in the previous embodiment, thisembodiment also eliminates end plate 15 of the previous embodiment,provides an assembled structure of first and second ducts 105 and 106whose disconnection allows the separation of outer cylinder 13 fromcasing 102. First and second ducts 105 and 106 connect the internalspace of combustion chamber 11 to the space around heater 3, and thusplace heater 3 within combustion chamber 11. End plate 15, which servedas a lid in the previous embodiment, is replaced by casing 102 which, inthis embodiment, contains heater 3 and functions as the lid ofcombustion chamber 11. Therefore, casing 102 may be movably mounted toframework 8 through slide rails 29. Ducts 105 and 106 may be separatedand casing 102 slidably moved on framework 8 in a direction away fromcombustion chamber 11 in order to expose heater 3 for maintenance work.

This embodiment provides the same operational effects as the previousembodiment, and may, of course, be used together with heating furnace 71described in FIG. 7 and thermal plant 97 described in FIG. 8. Eventhough Stirling engine 4, which includes heater 3, is completely housedwithin casing 102, in case casing 102 may partition combustion chamber11 into compartment, heater 3, though housed in casing 102, is stillable to be placed within combustion chamber 11.

The Stirling engines 4 and 80 described in these embodiments operatethrough the heating of heaters 3 and 79, and need not be of any specificstructure or shape. Furthermore, it is preferable that the operation ofthe gas supplying devices, such as the oxygen condenser, be used in thelate evening when the price of electricity is reduced.

The cogeneration system described by the invention is equipped with aStirling engine heater located within a combustion chamber, the internalregion of the combustion chamber being heated by combustion generated bya burner, and a liquid medium jacket enveloping the combustion chamber.The exhaust gas generated by the burner-driven combustion flows againstthe Stirling engine heater which is located in a position opposing theburner, and then flows through an exhaust gas flow channel into anexhaust gas passage which transfers thermal energy to the liquid mediumin the liquid medium jacket. Therefore, the exhaust gas from a singlecombustion chamber is able to simultaneously transfer thermal energy toboth the heater and liquid medium which can be applied to a thermalutilization process. This structure is able to transfer thermal energyfrom burner-generated combustion to both the heater and liquid mediumwithout employing space, time, or mechanically based heat transfermeans, thus making it possible to transfer thermal energy with highefficiency and no thermal loss, and to drive a highly efficientcogeneration system utilizing a thermal energy source.

This application is based on the Japanese Patent Application No.2003-028483 filed on Feb. 5, 2003 entire content of which is expresslyincorporated by reference herein.

The invention claimed is:
 1. A cogeneration system, comprising: acombustion chamber; a burner installed to said combustion chamber, andinducing exhaust gas-generating combustion within said combustionchamber; a liquid media jacket enveloping said combustion chamber andcontaining a liquid medium to be flowed therethrough, the liquid mediumbeing heated by the exhaust gas generated by said burner; a Stirlingengine having a heater installed within said combustion chamber anddisposed in opposite to said burner so as to be struck by the flow ofexhaust gas in said combustion chamber, and being operated by means ofbeing supplied a thermal energy from said heater to an operating fluidsealed therein; an exhaust gas flow channel discharging exhaust gaswhich flows toward said heater from said burner and supplies the thermalenergy to said heater; and an exhaust gas passage having an inletconnected to said exhaust gas flow channel and directing the flow ofexhaust gas along said liquid medium jacket; wherein the exhaust gasgenerated by burner-driven combustion flows against said heater as meansof transferring the thermal energy thereto, and then flows into saidexhaust gas passage, via said exhaust gas flow channel, as means oftransferring the thermal energy to the liquid medium, thereby providinga mechanism through which the exhaust gas is able to simultaneouslytransfer the thermal energy to said heater and the liquid medium.
 2. Thecogeneration system of claim 1, wherein a casing is provided as means ofenclosing at least said heater of said Stirling engine and defining atleast one of spaces forming said combustion chamber.
 3. The cogenerationsystem of claim 1, wherein an electrical generator is connected to anoutput shaft of said Stirling engine.
 4. The cogeneration system ofclaim 1, wherein a supply device is connected to said liquid mediumjacket as means of supplying the heated liquid medium to a thermalenergy utilization process.
 5. The cogeneration system of claim 1,wherein a heat absorbing and discharging thermal accumulator isinstalled within said combustion chamber.
 6. The cogeneration system ofclaim 5, wherein said thermal accumulator is disposed in opposition tosaid burner as means of allowing a burner flame and exhaust gas emittedfrom the burner-generated combustion to strike said thermal accumulator.7. The cogeneration system of claim 1, wherein a constricting part isinstalled within said combustion chamber as means of accelerating theflow of exhaust gas blown against said heater.
 8. The cogenerationsystem of claim 1, wherein said Stirling engine is equipped with aregenerator as means of cooling the operating fluid, and a coolantheated by the operating fluid through the operation of said regeneratorheats the liquid medium.
 9. The cogeneration system of claim 1, whereinan open and closable door is installed to said combustion chamber asmeans of exposing and sealing an internal region of said combustionchamber.
 10. The cogeneration system of claim 9, wherein said burner isattached to said door.
 11. The cogeneration system of claim 1, wherein aremovable lid is attached to said combustion chamber, and said heater ofsaid Stirling engine is attached to said lid.
 12. The cogenerationsystem of claim 1, wherein various types of virgin oils, liquid refuse,waste gasses, solid waste materials, biomass fuels, or mixtures of anyor all of these substances are used as fuel for said burner.
 13. Thecogeneration system of claim 1, wherein all types of virgin oils, liquidrefuse, waste gasses, solid waste materials, biomass fuels, or mixturesof any or all of these substances are used as a base fuel material towhich water is added in order to make an aqueous emulsion fuel forsupply to said burner.
 14. The cogeneration system of claim 13, whereinthe aqueous emulsion fuel is supplied to said burner from a fuelpreparation unit, said fuel preparation unit comprising: a mixing tankincorporating an agitator which agitates and mixes the base fuelmaterial with water and a surfactant, the resulting liquid mixture beingheld in said mixing tank; an emulsifier emulsifying the liquid mixturesupplied from said mixing tank; an ionizing unit ionizing watermolecules in the liquid mixture supplied from said emulsifier; and apump circulating the liquid mixture from said mixing tank to saidemulsifier, then to said ionizing unit, and then back to said mixingtank.
 15. The cogeneration system of claim 1, wherein an exhaust gassystem of a separate process is connected to said burner as means ofre-combusting an exhaust gasses generated by said separate process. 16.The cogeneration system of claim 15, wherein said exhaust gas system isstructured of two ducts, one duct being connected directly to saidburner, and the other duct being connected to said burner through awashing device which removes soot and ash from the exhaust gas.
 17. Thecogeneration system of claim 1, wherein a combustion gas supplied tosaid burner is a pure oxygen gas or an oxygen rich gas.
 18. Thecogeneration system of claim 1, wherein the fuel supplied to said burneris a mixture of oxygen and hydrogen gas.
 19. The cogeneration system ofclaim 1, wherein said burner includes: an igniter, a nozzle with aspraying end that separately sprays out fuel and a primary gas which mixat a location external to said spraying end, a secondary gas supplysystem that sprays a secondary gas into a mixture of fuel and primarygas as means of imparting a spinning motion to the mixture of fuel andprimary gas, a gasification duct that gasifies the fuel in the spinningmixture of primary gas and fuel flowing therethrough, and an oxidizinggas supply passage which supplies oxidizing gas to an outlet of saidgasification duct, in order to ignite and combust the fuel.
 20. Thecogeneration system of claim 19, wherein said burner includes a doublewall cylindrical structure at said spraying end of said nozzle, saidcylindrical structure being formed from an inner cylinder enclosedwithin an outer cylinder, said gasification duct being formed of a spacewithin said inner cylinder, and said oxidizing gas supply passage beingformed by a space within said outer cylinder.
 21. The cogenerationsystem of claim 15, wherein an exhaust gas heating furnace is installedto said exhaust gas system.
 22. The cogeneration system of claim 21,wherein said heating furnace is equipped with a second combustionchamber through which exhaust gas flows, and a second burner installedwithin said second combustion chamber as means of combusting and heatingthe exhaust gas.
 23. The cogeneration system of claim 22, wherein thefuel supplied to said second burner is any type of virgin oils, a liquidstate waste product, a gas state waste product, a solid state wasteproduct, biomass fuel, or a mixture of any of these substances.
 24. Thecogeneration system of claim 22, wherein the fuel supplied to saidsecond burner is any type of virgin oils, a liquid state waste product,a gas state waste product, a solid state waste product, biomass fuel, ora mixture of any of these substances used as a base fuel to which wateris added to make an aqueous emulsion fuel.
 25. The cogeneration systemof claim 22, wherein a combustion gas supplied to said second burner isa pure oxygen gas or an oxygen rich gas.
 26. The cogeneration system ofclaim 22, wherein the fuel supplied to said second burner is a mixtureof oxygen and hydrogen gas.
 27. The cogeneration system of claim 22,wherein said heating furnace is equipped with a second Stirling enginewhich has a second heater installed within said second combustionchamber and operates from a thermal energy supplied by said secondheater heated by the second burner-driven combustion, an output shaft ofsaid second Stirling engine being connected to a second electricalgenerator.
 28. The cogeneration system of claim 27, wherein a secondconstricting part is installed within said second combustion chamber asmeans of accelerating the flow of exhaust gas therein against saidsecond heater.
 29. The cogeneration system of claim 27, wherein a secondremovable lid is attached to said heating furnace, and said secondheater of said second Stirling engine is attached to said second lid.30. The cogeneration system of claim 15, wherein an exhaust gas heatingthermal plant is installed to said exhaust gas system, said thermalplant comprising a plurality of heating furnaces mutually interconnectedby ducts in an inline configuration.
 31. The cogeneration system ofclaim 30, wherein said thermal plant, in addition to said ductsinterconnecting a plurality of heating furnaces in the inlineconfiguration, is equipped with bypass ducts, each bypass duct bypassingeach heating furnace.
 32. The cogeneration system of claim 30, whereinat least one of said plurality of heating furnaces is equipped with aStirling engine which has a heater to be heated and operates from athermal energy supplied by said heater, an output shaft of said Stirlingengine being connected to an electrical generator.